Dual production zone pump



June 23, 1953 c. A. MoRRls ErAL DUAL Paonuc'rxon zona Puur dA. MoRRlsE'rA'i; I

DUAL PRODUCTION ZONE PUIIP June 23, 1953 2 Sheets-Sheet 2 Filed April27, 1950 @M3U ma;

AVG ENT.

Patented June 23,y 1953A DUAL PRODUCTION ZONE PUMP Charles A. Morris andJohn D. Exner, Wichita Falls, Tex., assignors, by mesne assignments, toStandard Oil Development Company, Elizabeth, N. J., a. corporation ofDelaware Application Aprilk27, 1950, Serial No. 158,368

The present invention relates to deep well pumps of the reciprocatingtype. More particularly the invention relates to an improved combinationof elements forming a unitary pump capable of pumping fluidssimultaneously from spaced, subsurface formations while maintaining thepumped fluids segregated from each other.

It is known to pump fluids, such as oil or water, from spaced producingformations either by employing a plurality of single zone pumps arrangedin a plurality of different boreholes or by employing a unitarystructure employing a plurality of pumps in av single borehole with eachpump withdrawing fluid from a dilerent sub# surface formation.Ordinarily it is impractical to pump uid from more than two pay zones bymeans of a single unitary pump structure.

Deep-well, dual-zone pump structures of the prior art have suiered fromthe disadvantages of being constructed in such fashion that, if, afterinstallation in a well, it becomes necessary to service the lower zonepump, the entire structure, including the production tubing string, mustbe withdrawn from the well; or the pump structure has included acomplicated and expensive packing arrangement for isolating the internaloperating zones of the pumps.

It is one object of the present invention to provide, in a unitarystructure, an` improved deep-well pump adapted to pumpk fluidssimultaneously from two, spaced subsurface formations without admixingthe fluids pumped from the two formations.

It is another object of the present invention to provide a dual-zonepump structure so constructed and arranged that the traveling elementsof both pumps may bewithdrawn fromv the well for servicing withoutdisturbing the tubing string on which the pump structure is normallysuspended inthe well.

It is a further object of the present invention to provide a simple andinexpensive means for sealing the internal operating zones between tworeciprocating pumps aligned in a unitary, deepwell pump assembly.

Still other and further objects of the present invention will becomeapparent from the following description taken in conjunction with theaccompanying drawings in which:

Fig. 1 is an elevation View, partly in section, of the upper portion ofone embodiment of a dual-zone pump assembly constructed in accordanceAwith our invention, and showing an upper production zone pump;

Fig. 2 is an elevation View, partly in section, of

3v Claims. (C1. 10S-4) Atubing string I1.

'a next lower intermediate portion of the ernbodiment shown in Fig. 1and showing a seal barrel and plunger in accordance with our inventionfor sealing the internal operating zones between pumps;

Fig. 3 is an elevation view, partly in section, of a still lowerintermediate portion of the embodiment illustrated in Figs. l and 2,and. showing! a casing-tubing packer for sealing between two producingformations;

Fig. 4 is an elevation view, partly in section, of the lower portion ofthe embodiment Shown in Figs. 1, 2 and 3, and showing particularly alower production zone pump; and

Fig. 5 is a cross-sectional. view taken along the line V-V of Fig. 1.

In the several Views, like numerals refer to like parts of the assembly.

In the drawing., the numeral. Il designates the walls of aborehole whichpenetrates subsurface earth formations includingtwo producing formationsor zones, such as an upper' zone I2 (Figi) and a lower zonerv I3 (Fig.4)`. In usual practice, the borehole will be cased by a'casing string I4which is supported. at the well head (not shown) ra, stationary,production tubing string II which, `similar to casing I4, is supportedin the well head in conventional manner.

In accordance with a preferred embodiment of vour invention, a tubularhead member or sub I8,

provided with a central longitudinal passage I9, is screw-threadedlyengaged to the lower end of The lower end of head member I8 has asubstantially larger outside diameter than tubing string I1 and isthreadedly secured to the upperend of a rst, or upper, tubular jacketY20, which also is of larger diameter than tubing I'I. Jacket 20 isconstructed of suflicient length to house an upper production zone pumpwhich will be described more fully hereinafter,

Screw-threadedly engaged to the. lower end of jacket 20' is a firstcoupling member 2| which,

as will' become apparent from subsequent description, serves also as ananchor member for the upper zone pump. Depending from, andscrew-threadedly engaged to, the lower end of member 2`I is va second,or intermediate ltubular seal barrel which will be subsequentlydescribed. At the lower end of jacket 22, a second coupling member orsub 23 is screw-threadedly engaged thereon. Coupling member 23 isprovided with a central longitudinal passage 24 and, preferably, istapered at its lower end to a smaller external diameter than jacket 22.Secured to the lower end of member 23, as by screw threads, is a third,or lower, tubular jacket 25 which -terminates in a conventionalbottom-lock releasable pump hold-down device 26 provided with alongitudinal iiuid passage 21 such, for example, as the pump anchorshown and described in the Kelly et al. Patent, 2,298,567. Tubularjacket 25 is constructed at least of sufficient length to house a lowerzone pump, which will be described hereinafter, and will preferablyterminate adjacent or below lower producing formation I3. If desired,any suitable form of well screen or mud anchor may be secured to thelower end of pump anchor 2S. In the drawing, a perforated tubing nipple28 has been shown to represent such a means for admitting lower zonefluid.

It will be understood that jackets 20, 22, and 25 may be constructed ofconvenient lengths of suitable diameter tubing coupled together atintermediate points, as needed, by conventional collars not specificallypointed out hereinabove. Although, for convenience in description,mernbers 20, 22 and 25 have been described as three different jackets,it will be apparent that these members are so joined together that theymay also be considered as forming a single jacket assembly for a unitarystructure. While the members 22, 23, and 25 form parts of a singlejacket assembly, upon consideration it may be seen that these members,in combination with the pump anchor 26, also serve as means forsupporting the lower pump at a selected distance below the upper pump.As may be seen from the drawing, all of these members are aligned alonga common central axis.

Around the jacket structure, at a position between producing formations|2 and I3, and preferably within casing |4, there is disposed aconventional packer means 29, as shown in Figure 3. Although a cup-typecasing-tubing packer has been illustrated in the drawing, it will beunderstood that packer means 29 may be any suitable packer adapted toseal between the jacket and the casing I4, or between the jacket and thewalls of an uncased borehole intermediate between producing formationsI2 and I3 to prevent intermixing of formation fluids external to thepump assembly.

Secured to pump anchor 26, as by means of pull tube 30 and collar 3|, isa lower tubular plunger 32 provided with suitable circumferentialpacking rings, or cups, 33 and a conventional standing valve means 34.Reciprocatably sliding over plunger 32 and packing means 33, is a lowerpump traveling barrel provided at its upper end with a conventionaltraveling valve means 36 and open valve cage 31. Secured 'to the lowerend of barrel 35 and concentrically around pull tube 30 is a sleeve orbushing 38, adapted to engage against collar 3l during an extreme upwardpull transmitted to barrel 35 when it is desired to release hold-downmeans 26 from its anchored position and thereby remove plunger 32 fromits normal operating position. Since the structure and the operation ofa suitable pump anchor 25 is well known in the prior art, furtherdescription thereof is omitted herein.

From the foregoing description it may be seen that the working barrel 35and its associated traveling valve structure 36, 31 form a cylindricalreciprocating element in the lower pump, while the plunger 32, withassociated packing means 33 and standing valve means 34, form acylindrical stationary element which co-operates with the reciprocatingelement to pump a fluid. It will be apparent to workers in the art,however, that by suitable rearrangement of the standing and travelingvalves, the above-described pump may be inverted so that the workingbarrel is held stationary by anchor means 26, and the plunger 32 may becaused to reciprocate therein. The plunger will then be the cylindricalreciprocating element in the lower pump.

As may be seen from Fig. 4 of the drawing, an upward stroke of barrel 35causes lower formation fiuid to be drawn through well screen or tubingnipple 28, fluid passage 21, the bore of pull tube 30, the bore oftubular plunger 32, and thence through standing valve means 34 into theinterior of barrel 35. When barrel 35 is forced downward, valve means 34closes, valve means 36 opens, and the fluid within barrel 35 is forcedinto the bore of tubular jacket 25 above valve 36.

In order to impart longitudinal reciprocating motion to barrel 35, afirst sucker rod string 39, arranged substantially concentrically withinjacket 25 and the central passage 24 of coupling member 23, isthreadedly secured to cage 31 which, in turn, is suitably secured tobarrel 35. The upper end of rod string 39 is threadedly secured to thelower end of a valveless blind plunger 40.

Plunger 4] is constructed with a slightly1 larger outside diameter thanthe outside diameter of traveling barrel 35, and is provided withsuitable circumferential packing rings or cups 4|. Plunger 4I! andpacking means 4| are arranged to reciprocate longitudinally in anelongated tubular seal barrel 42 and, in combination with the latter, toprovide an effective, movable seal between the internal operating zonesof the lower pump, described hereinabove, and an upper pump, to bedescribed hereinafter.

Seal barrel 42, as may be seen from Figs. 1 and 2, is screw-threadedlysecured in the lower portion of centralpassage 43 in coupling member 2|,and is seated, or otherwise suitably retained, in an enlarged upperportion of central passage 24 in coupling member 23. Adjacent tocoupling member 23 and the lower end of seal barrel 42, the latter isprovided with one or more iiuid ports 44 adapted to pass the pumpedlower zone iiuid from the bore of jacket 25 and central passage 24 intoa first annular passage 45 defined between the outer walls of sealbarrel 42 and the inner walls of jacket 22. As may be seen from Figs. land 2, annular passage 45 extends throughout the length of jacket 22between coupling members 2| and 23.

Secured to the upper end of blind plunger 40, as by screw threads orother suitable means, is a second sucker rod string 46 which passesupwardly through central passage 43 in coupling member 2| and terminatesin a yoke 41.

In the drawing of Fig. l, coupling member 2| has been shown in sectiontaken along the section line I-I of Fig. 5. Similarly, in the drawing ofFig. 5, coupling member 2| has been shown as a section taken along theline V-V of Fig. l. As may be seen from these figures, coupling member2| is provided with a plurality of bypass passages 48 extendinglongitudinally therethrough and providing communication between iirstannularpassage 45 andv a, second annular passage 49 dened. between theouter wal-1sV of a stationary upper pump working barrel 5I)v and theinner wal-ls. of jacket 26. The lower end of upper pump working barrel5111 is" screw-threadedly Secured, Vand thereby anchored,v in. couplingmember 2|` intheav upper endv of central passage'43, whilev theupper-endA of said barrel. is seatech4 or otherwise secured, inthecentral. passage I9 of head member I6. One or more' iluid re-entryports5l. areprovided adjacent the upper end of work-ing barrel 5B toprovide means fori passing pumped lower zone flu-id. out ofannular-passage 49 into passage I9 and thence into tubingstring I1.

The outer walls of' coupling member 2| are pierced by a plurality ofupper zoney uid entry ports 52. which communicate,r through suitablescreens 53- and upper pumpstanding valve.` means 54, with a plurality ofports 55 entering central passage 43. Thus, upper zone V fluidy. drawnthrough perforations I6 in casing stringk I4, enters ports 52., passesIthrough. screensl 53` and standing valves 54, and. enters centralpassage-'43 through ports 55.

Although, for convenience of description, the member 2J hasbeen termed acoupling member by virtue. of: its utilization tocouple jacketpump. Whenconsidered thus,- vthe threaded juncture between seal barrel'. 4,2.and;l member 2l provides. a means for sealing saidY seal barrel to saidcylinder structure. I

Arranged' for longitudinal reciprocating move;- ment in working barrel5llis ai movable upper pump plunger 56 provided with circumferentialpacking rings or cups; 51;. Blunger 56 istubular, thereby permittingpassage.I ofy uidpgthrough, central. bore 5BV therein. At.: itslower'end'fplunger `56 is secured to yokeV 4l., as bylSuitable.l screwthreads. Ports 59. are provided in. yoke. 4lv so that uid in the lower.part of working barret 5.0 mayv enter.v bore. 58 of. plungeri5'6rArranged along bore58 orplunger anduit.- ably secured thereim isatraveling. valve means 60. Secured to the upper end. of plunger tfandabove-,valve meansV 60,A is a, bushing' 6i which .com nects. theplungerto amovable tubingxstring: 62, Tubing 6,2 passes. upwardlyrr throughpassage [9. in head member I8., and, thencegsub'stantially con.-centrically within and through-.stationary tubing string II.

The upperv end of movabletubingHr string .6.2 passes through aconventional Stuffingbox' above the well head and may be connected;through a flexible connectionto a ilow line. Tubing string gitudinally,the` resulting reciprocating movement is imparted to pump plunger 5.6,vsecond sucker rod string 46, blind plunger-41),.iirstsuck,- er rodstring. 3.9 andlower pump traveling barrel 35, simultaneously. 'IlxeseAelemente; taken as a 6 unit; 'formy ak common reciprocatingl lmemberwhich.. is operatively connected vto each of. tw@ pum-ps.. Intheoperation-of the. pump.- assembly of our invention.. lower zone fluidwhich has beenrforced intol the-.bore of lower jacket 25, ask has beenhereinbefore described, is forced upward through central passage 2.4- incoupling member 23, through fluid ports 44 in` seal barrel 42., and intoannular passage 45. Continued operation .of the pump assembly forces..the iluid in. annular passage 45 upward through by-pass` passages 48 in.coupling member 2 I, then through they second annular passage 49, fluidre-entry ports 5iI in working barrel 50, and thence into stationaryproduction tubing I.'I.. Because of the presence of. seal; barrel 42,blindL plunger 40. therein, upper pumpV working barrel 50, and upperpump plunger 56. lower zonev fluid cannot intermix `with uid drawn intothe upper zone pump.

As may be seen from Fig. l, when plunger 56 isY movedupward, upper zonefluid enters through perforations I 6, entry ports 52, screens 53,standing valve means 5.4, ports 55, central passage 4.3 and. into the bore of working barrel 50.. 'Thereafter, when plunger 56I is moveddownward, valve means 54 closes, traveling valve means 60 opens andupper zone Iluid is forced upward through ports 59, central borev 58,.valve means 60. and thence into the bore of tubing 62.

From. an examination. of Figs. 1 and 2, it may be seen that the upperzone pump operates on the principle of differential displacement of thetwo plungers, 40 and 56, on opposite sides of a valved, fluid-entry port55. The bore of'workingy barrel 50 must be greater than the bore of sealbarrel 42 in order'to obtain fluid delivery from. the upper zone. pump.By lsuitable choice of the internal diameters of these barrels, thevolumetric delivery of. the upper zone pump may be adjusted.

`In accordance with one objective of the device of our invention,thebore of tubing string II is. also constructed of greater diameterthan the. outside-- diameter of upper pump plunger 56, thehoreofworkingy barrel 50 vis of greater diameter than the outside diameter ofblind plunger 40, and the bore. of central passage 43, seal barrel. 42,and central passage 24 are greater than the outside diameter of lowerpump traveling barrely 35 so that, when it is desired to serv- 4iceeither the upper zone pump traveling elements or thelower zonev pump,the movable tubingstring 62 may be pulled. upward for a greaterdistance. than the normal operatingk stroke'. Thereafter, tubing string62 may be drawn upward out of the well. followed by the other elementsincludingplunger 56, sucker rods 46,l blind plunger 40,.sucker rods 35,traveling. barrel .35,

plunger 32., and the releasable portion ofv pump anchor 26..

It, may be Vseen that, by lemploying moving blind plunger 40 sealinglyreciprocatable in iixed seal barrel 42, expensive and troublesomelatching means,` for retaining inter-pump packing means in position is.eliminated and the lower zone. pump` may be. removed from the well;with.- out withdrawing the; tubing string I.'I andthe pump jacketsvdepending therefrom.

As will be apparent the lengthstof tubingV H, jacket 20, jacket 22,jacket 25., sucker rod string 39, sucker rod string 46, andmovabletubing string 62. may be varied to suit theparticular ydepths andspacingl of producing. formations I2 and"|3 lbeneath the surface oftheearth. First coupling member 2l ordinarily will be installed abovepacker 29 and below the normal standing level of liquid derived fromformation I2, while the lower zone pump, and especially the standingvalve therein, will generally be installed below the normal standinglevel of liquid derived from formation I3.

Although our invention has been described with respect to a singleembodiment thereof, it will be understood that modifications and changesmay be made without departing from the scope of the appended claims. `Itis, therefore, to be understood that our invention is not to be limitedto the specific details shown and described herein.

Having thus described our invention, what we claim as novel, and desireto secure by Letters Patent. is:

1. A dual zone pump assembly adapted to pump fluid simultaneously fromlower and upper subsurface zones without intermixing the fluid from saidzones comprising, in combination, a tubular head member, defining acentral passage therethrough, adapted to be threadedly secured to thelower end or" a stationary tubing string within a suitably perforatedcasing string in a borehole; a first tubular jacket threadedly secureddependently from said head member; a first coupling member defining acentral longitudinal passage and at least one longitudinal by-passpassage therethrough, and also defining an upper zone entry portarranged to provide ingress of fluid from said upper zone into saidcentral passage, said coupling member threadedly joining the upper endof a second tubular jacket coliinearly to the lower end of said rstjacket; a

second coupling member, defining a central longitudinal passagetherethrough, threadedly joining the upper end of a third tubular jacketcollinearly to the lower end of said second jacket; means adjacent thelower end of said third jacket for admitting fluid from said lower Zoneinto the interior of said third jacket; a releasable lock hold-downmeans, provided with a longitudinal fluid passage therethrough,positioned within said third jacket and above said fluid admittingmeans; a lower tubular plunger', provided with suitable circumferentialpacking rings in the outer walls thereof, secured to said hold-downmeans coaxially within, and spaced from, said third jacket; a lower pumpbarrel arranged for reciprocating movement concentrically over saidlower plunger; standing valve means in said lower plunger and travelingvalve means in said lower pump barrel constructed and arranged tocooperate and deliver fluid above said lower pump barrel upon downwardmovement of the latter; packer means secured circumferentially aroundsaid third jacket below the upper extremity thereof and adapted to sealolf an annular space defined between said third jacket and said casingstring; a tubular seal barrel, defining at least one fluid port throughthe wall and adjacent the lower end thereof, seated in the centralpassage of said second coupling member and threadedly secured in thecentral passage of said first coupling member whereby an annular passageis provided between said seal barrel and said second jacket; a blindplunger, provided with suitable circumferential packing means slidablyengaging inner walls of said seal barrel, arranged for longitudinalreciprocating movement concentrically within said seal barrel; a rstsucker rod string securing the lower extremity of said blind plunger tothe upper extremity-of said lower pump barrel; a stationary upper pumpbarrel, defining at least one fluid reentry port adjacent its upperextremity, threadedly secured at its lower end in thel central passageof said first coupling member and seated at its upper end in the centralpassage of said head member whereby an annular passage is providedbetween said pump barrel and the rst tubular jacket; a movable upperpump plunger', defining a central bore and having suitablecircumferential packing means in the outer walls thereof slidablyengaging inner walls of said upper pump barrel, arranged forreciprocating movement concentrically within said upper pump barrel;standing valve means in the upper zone entry port of said first couplingmember and traveling valve means in said upper pump plunger constructedand arranged to cooperate and deliver fluid above said traveling valveupon downward movement of the uper pump plunger; a second sucker rodstring securing the upper end of the blind plunger to the lower end ofthe upper pump plunger; and a movable tubing string adapted toreciprocate substantially conoentrically within said stationary tubingstring, threadedly secured to said upper pump plunger above thetraveling valve means therein.

2. In a dual zone pump assembly adapted to be' secured to the lower endof a tubing string in a well having upper and lower fluid-producingzones wherein said pump assembly comprises an elongated jacket assemblycarrying an upper reciprocating pump and a lower reciprocating pumptherein; and wherein said upper pump includes a cylindrical workingbarrel secured to the jacket assembly, a valved piston slidably engagingthe interior walls of the working barrel, and upper standing valve meanscarried in fluidentry ports formed in said jacket assembly below theworking barrel and above the lower pump; and wherein said lower pumpincludes a reciprocating part carrying a traveling valve, a stationarypart carrying a lower standing valve, and releasable anchor means foranchoring the stationary part to the lower end of the jacket assembly;the improved means for segregating internal operating zones of saidupper and lower pumps which includes an elongated cylindrical sealbarrel secured to the jacket assembly below the upper standing valve andabove the lower reciprocating pump, said seal barrel having an internaldiameter smaller than the external diameter of said valved piston andlarger than the external diameter of said lower pump, a blind plungerslidably engaging interior walls of the seal barrel; rod memberssecuring the blind plunger, in suitable spaced relation, to the valvedpiston in the upper pump and to the reciprocating part in the lowerpump; said tubing string, said upper pump working barrel, said sealbarrel, and the lower portion of said jacket assembly dening anunimpeded passageway whose internal diameter is proportioned stepwiselysmaller in the downward direction whereby said valved piston, blindplunger, and lower reciprocating pump may be withdrawn upwardly from thejacket assembly upon release 0f the anchor means of the lower pump.

3. A deep-well pump assembly including, in combination, a rstreciprocating pump comprising an elongated cylinder structure and apiston slidably engaging interior walls thereof; a seoond reciprocatingpump comprising a cylindrical reciprocating element and a concentricstationary element co-operatively associated therewith 9 to pump afluid; means supporting said second pump coaxially at a selecteddistance below said first pump along a central axis common to bothpumps; a rod member secured axially to the lower end of said piston andto the upper end of said cylindrical reciprocating element fortransmitting reciprocating movement of the former simultaneously to thelatter; an elongated cylindrical seal barrel spaced concentricallyaround said rod member between said first and second pumps, the internaldiameter of said seal barrel being greater than the external diameter ofsaid second pump and less than the internal diameter of said cylinderstructure; means sealing the upper end of said seal barrel to the lowerend of said cylinder structure; and a blind plunger se- 10 curedcoaxially around said rod member Within said seal barrel and slidablyengaging interior walls of the latter.

CHARLES A. MORRIS.

JOHN D. EXNER.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 2,281,899 White May `5, 1942 2,499,356 Coberly Mar. '7, 19502,499,357 Coberly Mar. 7, 1950 2,513,869 Hofer July 4, 1950 2,522,825Hoier Sept. 19, 1950

